There are many different known surgical retractor components, for example, halo-style retractors and supporting components as well as flexible retractor arms. Halo-style retractors are often made of two hinged, generally semicircular half-rings, a first of which is affixed to supporting structure. A second half-ring is pivotable and adjustable with respect to the first half-ring about a generally diametric axis of rotation. Retractor arms and other attachments are attachable to the half-rings via an internal dovetail slot extending along an outer directed surface of the half-rings. The halo-style retractor is mounted on a cranial stabilization device, for example, a skull clamp, and its position and orientation are adjustable to meet the needs of the surgical procedure. Often the skull clamp is radiolucent and may, in turn, be mounted on a radiolucent patient support structure such as an operating table extension.
The components of such halo-style retractors are usually fabricated from stainless steel or other metals. One problem with such halo-style retractors is that the metal is radiopaque to x-ray and other imaging processes, and such metal parts produce “artifacts” in resulting images. These artifacts diminish the usefulness of the imaging process because they often obscure an image of a portion of a patient that normally would be viewable, absent the obscuring radiopaque retractor arm, halo-type retractor and supporting components. Further, more and more surgical procedures are requiring interoperative scanning procedures, and the use of radiopaque retractor components complicates such procedures. For example, one option is to remove the radiopaque equipment prior to the scanning process. As will be appreciated, that option is not often possible in an interoperative procedure. Another option is to position and orient the radiopaque retractor components so that they still provide the desired surgical function but also minimize artifacts and interference in portions of a scanned image that are of interest to a surgeon. This option is at best, difficult, time consuming and provides only a limited benefit, and at worst, the option is practically not available.
Therefore, there is a need for a radiolucent retractor arm, a radiolucent halo-type surgical retractor and a radiolucent retractor support structure that minimize artifacts in an imaging process.